Which statement best distinguishes TTP from HUS and indicates the main treatment?

Which statement best distinguishes TTP from HUS and indicates the main treatment?

• A. HUS has renal involvement; Plasma exchange is not used.
• B. Plasma exchange is main treatment for HUS.
• C. TTP features microangiopathic hemolytic anemia and neuro symptoms.
• D. Platelet transfusion is main treatment for TTP.

Answer: (C)

The key idea here is distinguishing TTP from HUS by the pattern of organ involvement. Thrombotic thrombocytopenic purpura (TTP) classically presents with microangiopathic hemolytic anemia along with neurologic symptoms such as confusion, seizures, or other neuro signs, reflecting brain involvement from microthrombi. Hemolysis with red-blood-cell fragmentation (schistocytes on smear, elevated LDH, low haptoglobin) plus neurologic involvement points toward TTP rather than HUS. Hemolytic uremic syndrome (HUS) more typically features prominent kidney injury (acute renal failure) with less prominent neurologic symptoms. That distinction matters because the treatment approach for TTP is urgent plasma exchange, which removes autoantibodies against ADAMTS13 and replenishes the enzyme, reducing mortality. Platelet transfusion is not the main treatment for TTP and can worsen microvascular thrombosis. In HUS, management is more supportive, with plasma exchange reserved for atypical cases or specific etiologies and other targeted therapies used as indicated. So the statement that best distinguishes TTP from HUS is that TTP features microangiopathic hemolytic anemia and neuro symptoms.

The key idea here is distinguishing TTP from HUS by the pattern of organ involvement. Thrombotic thrombocytopenic purpura (TTP) classically presents with microangiopathic hemolytic anemia along with neurologic symptoms such as confusion, seizures, or other neuro signs, reflecting brain involvement from microthrombi. Hemolysis with red-blood-cell fragmentation (schistocytes on smear, elevated LDH, low haptoglobin) plus neurologic involvement points toward TTP rather than HUS. Hemolytic uremic syndrome (HUS) more typically features prominent kidney injury (acute renal failure) with less prominent neurologic symptoms.

That distinction matters because the treatment approach for TTP is urgent plasma exchange, which removes autoantibodies against ADAMTS13 and replenishes the enzyme, reducing mortality. Platelet transfusion is not the main treatment for TTP and can worsen microvascular thrombosis. In HUS, management is more supportive, with plasma exchange reserved for atypical cases or specific etiologies and other targeted therapies used as indicated.

So the statement that best distinguishes TTP from HUS is that TTP features microangiopathic hemolytic anemia and neuro symptoms.